1. Field of the Invention
The present invention relates to a method for fabricating a liquid crystal display device, and more particularly, to a method for fabricating a liquid crystal display device, which can improve step coverage of an insulating layer included in a substrate in which a plurality of conductive layers and insulating layers are stacked, thereby preventing wire breakage in the conductive layer.
2. Discussion of the Related Art
Liquid crystal display devices display an image by regulating light transmissivity of liquid crystal, having a dielectric anisotropy property, using an electric field. Such a liquid crystal display device is mainly constructed in such a way that a color filter substrate, formed with a color filter array, and a thin-film transistor substrate, formed with a thin-film transistor array, are bonded to each other with liquid crystal interposed therebetween. The thin-film transistor substrate is provided with a plurality of pixel electrodes arranged in a matrix, a data signal being applied to the respective pixel electrodes individually. Also, the thin-film transistor substrate is provided with thin-film transistors to drive the plurality of pixel electrodes individually, gate lines to control the thin-film transistors, and data lines to apply a data signal to the thin-film transistors.
The thin-film transistor substrate is configured in such a way that a plurality of conductive layers and insulating layers are stacked. For example, the thin-film transistor substrate is configured in such a way that a first conductive layer, in which the gate lines, gate electrodes of the thin-film transistors, etc. are formed, a second conductive layer, in which the data lines, source electrodes and drain electrodes of the thin-film transistors, etc. are formed, and a third conductive layer, in which the pixel electrodes, etc. are formed, are stacked with insulating layers interposed therebetween.
The above-described thin-film transistor substrate includes a plurality of jumpers, which must connect the first and second conductive layers with each other by means of bridge electrodes formed of the third conductive layer. The bridge electrodes connect the first and second conductive layers with each other by way of first contact holes, which penetrate at least two insulating layers to expose the first conductive layer to the outside, and by way of second contact holes, which penetrate at least one insulating layer to expose the second conductive layer to the outside.
However, a semiconductor layer is further formed below the second conductive layer. As a result of stacking the second conductive layer over the semiconductor layer, the insulating layer formed on the second conductive layer exhibits poor step coverage at a stepped portion between the semiconductor layer and the second conductive layer. In this case, when the third conductive layer is formed on the insulating layer exhibiting poor step coverage, the third conductive layer has a problem of wire breakage.